This relates generally to electronic devices and, more particularly, to electronic devices with displays.
Electronic devices often include displays. For example, cellular telephones, computers, and televisions have displays.
Displays such as liquid crystal displays have arrays of display pixels. To enhance the visibility of images that are displayed on an array of display pixels, a display may be provided with a backlight. In a typical configuration, an array of light-emitting diodes emits light into the edges of a clear light guide plate. The light guide plate distributes the light laterally across the display. Light scattering features in the light guide plate help scatter the light outwards through the array of display pixels.
Conventional backlight arrangements such as these include additional layers to enhance performance such as a reflector to reflect inwardly scattered light outward through the display pixel array, diffuser layers for homogenizing backlight, compensation films to enhance off-axis viewing, and prism films that help collimate light from the backlight. These layers and other layers in a display may add undesired bulkiness, cost, and complexity. Efficiency losses may also arise due to the presence of black matrix structures in the color filter layer of a display that separate adjacent color filter elements.
It would therefore be desirable to be able to provide a backlight configuration that overcomes these issues.